Activated aging dynamics and negative fluctuation-dissipation ratios
Seminar Room 1, Newton Institute
In glassy materials aging proceeds at large times via thermal activation. We show that this can lead to negative dynamic response functions and novel and well-defined violations of the fluctuation-dissipation theorem, in particular, negative fluctuation-dissipation ratios. Our analysis is based on detailed theoretical and numerical results for the activated aging regime of simple kinetically constrained models. Our results are relevant to a variety of physical situations such as aging in glass-formers, thermally activated domain growth and granular compaction.